In rainy or snowy days, and in mountainous areas, in order to prevent automobile tires from slipping, an anti-skid chain needs to be set outside the tire. However, the existing anti-skid chains in motion show outstanding problems: 1. Installation on the tire is not very firm, which makes the chain easily loose and slip, affecting the safety of vehicles and pedestrians around. 2. The anti-slip effect is poor. 3. The anti-skid chains units appears suspending in the air and uneven loading capacity, which is easy to make the anti-skid units broken, destroyed and affecting its serving life. 4. The installation is complex and troublesome.